1. Field of the Invention
The present invention relates to electronic function circuits, and particularly to a compact CMOS current-mode analog multifunction circuit operating in the weak inversion region.
2. Description of the Related Art
Low power and low voltage current-mode analog computational circuits got an increasing interest lately especially as CMOS fabrication technology advances. Using current-mode circuits, many functions can be design with less number of components compared to the voltage-mode counterpart. Nowadays, low voltage and ultra-low power analog circuits are becoming mandatory in battery powered applications. CMOS circuits operating in subthreshold region can be used to realize a low voltage and low power circuits. Multiplication and division are important analog signal processing functions. Having such circuits that consumed very low power is a great advantage. That is because they can be used in portable devices especially devices that are to be used in remote areas. There are many approaches reported in the literature to design multiplier, squaring, square rooter and divider circuits.
Although there are many proposed circuits for current-mode analog multipliers and dividers, many of them are designed to work only as multipliers and dividers. Having a single circuit that can perform more than one function is preferable.
Thus, a compact CMOS current-mode analog multifunction circuit solving the aforementioned problems is desired.